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The Moon's Gravitational Pull Can Trigger Major Earthquakes, Says Study (nature.com)
schwit1 writes: A careful statistical analysis of when major earthquakes occur has suggested they are more likely to be more powerful if they occur around the full and new moons when tidal forces are at their peak. Nature.com reports: "Satoshi Ide, a seismologist at the University of Tokyo, and his colleagues investigated three separate earthquake records covering Japan, California and the entire globe. For the 15 days leading up to each quake, the scientists assigned a number representing the relative tidal stress on that day, with 15 representing the highest. They found that large quakes such as those that hit Chile and Tohoku-Oki occurred near the time of maximum tidal strain -- or during new and full moons when the Sun, Moon and Earth align. For more than 10,000 earthquakes of around magnitude 5.5, the researchers found, an earthquake that began during a time of high tidal stress was more likely to grow to magnitude 8 or above." As these results are based entirely on statistical evidence, not on any direct link between tidal forces and actual quakes, they are quite uncertain and unproven.
Well fuck the moon then, nuke the shit out of that rock.
The article doesn't say how much more likely major earthquakes are. For a large sample, even small differences are statistically significant and will result in very low p-values. For that reason, statistical significance doesn't necessarily indicate that the result is actually meaningful.
"The Moon's Gravitational Pull Can Trigger Major Earthquakes, Says Study".
No the fucking study does not say that at all, it says their is some correlation between the tidal stress and the size of earthquakes.
Well, it's actually the added stress from the Sun's alignment with Earth and Moon that's likely to play the major role here. The Moon itself doesn't do anything special during the full and new moons.
As these results are based entirely on statistical evidence, not on any direct link between tidal forces and actual quakes, they are quite uncertain and unproven.
Given that the article does not say tidal forces CAUSE quakes, this cushioning is completely unnecessary. They're only noting a suggestion of a link between tidal forces and the magnitude of the quake - not the occurrence/non-occurrence of a quake.
And something being "based entirely on statistical evidence" does not invalidate or weaken anything. It is the quality of the statistical evidence, not the mere use of statistical evidence, that would invalidate or weaken a claim.
Those who do not learn from commit history are doomed to regress it.
Do moonquakes occur during these periods?
There used to be a geologist on Coast to Coast AM (Art Bell's radio show) who always claimed that there was a relationship between the moon and earthquakes. He predicted the 1989 World Series quake and lost his government job. His name was Jim Berkland.
look up flat earth on youtube. trumps any tv show
Now witness the paawer of diss fully armed and operational battle station! Good, geuwd, you can now hear my voice, my young AppRenTist!
Yeah, but
"Study shows statistical correlation that might suggest that tidal stress could be among the dozens of other factors that each contribute slightly in favor of stronger earthquakes", though much more accurate, doesn't have the same "oomph" and thus doesn't manage to sell the same amount of eyeballs to the ad-company paying for this fucking article.
"The moon will kill with its earthquake power! Cower in terror!! Panic!!! Buy products to feel better!!!!" works so much better...
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
There's a lot less likeliness of Moonquales happening:
- The Moon, as mentioned by others is tidally locked with Earth.
i.e.: It's always the same side facing Earth
that means that Earth tidal stress is always "pulling" the exact same part.
thus no change in this "pull" and therefore no directly-earth-caused tides on the moon.
- The Moon is a huge solid rock, it doesn't move much, whereas the Earth is pieces of solid crust all covering a molten mantle on which they more or less float (the "more of less" part being when they bump into each other, rub against each other, or one dives under another).
Thus Earth has a tectonic seismology (the tectonic plate doing their above mentioned shit instead of peacefully floating next to each other), on which a whole bunch of factors (including in parts the tidal stress exerted by the Moon as maybe suggested by this study) can act as trigger to release to stored shear stress (causing Earthquakes).
Whereas the Moon, by being a solid block of rocks can't do that.
- On the other hand, the Moon has no atmosphere :
Any falling rock will smash straigh on the surface. Such meteorite contribute heavily on the moonquakes.
The part of the moon that face the Sun will be backed in light, while the other side will cool off a lot, and as the moon is tidally locked with Earth, such "Moon's days" take a whole full-moon cycle (2 weeks day, 2 weeks night). Such huge difference in "cooking" temperature can cause stress and also contribute to moonquakes.
(in both case the Earth is more or less innocent - except indirectly by tidal lock and/or "benefiting" from the moon as a giant meteor shield)
NOTE: I am a Doctor, not an Astrophysicist (in McCoy's voice). ...or I might be lying and covering moonquakes actually caused by nuclear tests done by the Nazis hidden on the dark side of the moon.
So I might be wrong.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
Solution: Destroy the moon!
Are you serious? The moon is in gravitational lock, so experiences no tidal stress.
Not actually true. Because Earth is not tidal locked to the moon, the rotation of the Earth will cause tidal stresses on the Moon because the Earth is not a uniform body, nor is the moon. Tidal locking does not equal no tidal stresses.
Have you not noticed that the same side of the moon always faces the earth?
Again not completely true. See lunar libration. The orbit of the moon is not circular, the Earth itself rotates and their respective axis of rotation are not identical. So we don't always see precisely the same face of the moon. We actually see about 59% of the moon's surface though not all at the same time.
OK, there is some tidal force from the sun, but the moon is also kind of small, and solid. No molten core, no ocean, no thin crust, no plate tectonics.
There also are some tidal forces from the Earth on the moon. The effect appears to be quite minor. Moonquakes are apparently a thing and apparently ARE caused at least in part by tidal interactions between the Earth and the Moon.
- The Moon, as mentioned by others is tidally locked with Earth.
i.e.: It's always the same side facing Earth that means that Earth tidal stress is always "pulling" the exact same part. thus no change in this "pull" and therefore no directly-earth-caused tides on the moon.
Incorrect. The Earth is not a uniform sphere and it is not (yet) tide locked to the Moon. The Earth does exert tidal stresses on the Moon because the gravitational pull on the moon is not uniform.
- The Moon is a huge solid rock, it doesn't move much, whereas the Earth is pieces of solid crust all covering a molten mantle on which they more or less float (the "more of less" part being when they bump into each other, rub against each other, or one dives under another).
That very malleability of the Earth is a big part of what causes tidal stresses on the Moon. Remember that tidal forces are simply the results of unequal gravity between two bodies. If the bodies aren't uniform the tidal forces by definition cannot be zero. Tidal lock does not mean no tidal stresses. In fact I'm pretty sure it is tidal stresses that create and maintain the tidal lock.
Since this was rated "interesting" instead of "funny", I can only assume that the people here actually believe this crock of s***. If someone actually bothered to compute the gravitational force on the Earth by both the sun and moon, you would find the force of the moon is about 1E6 times larger than that of the sun. I'm not going to do the computation here as I already did it about 30 years ago when we were quoting a highly accurate motion platform. I'll let someone else do the math and post the numbers here.
Can anyone explain to me why the phase of the moon would have anything to do with its gravitational pull?
"A plan fiendishly clever in its intricacies"- Homer Simpson
It's about time scientists started admitting that bad things DO happen at full moon.
and tell him to try to steal the moon again. :)
Can anyone explain to me why the phase of the moon would have anything to do with its gravitational pull?
The phase itself doesn't have any meaningful effect that I am aware of but the factors that cause the moon phase DO cause real changes in tides. Primarily orbit of the moon in relation to other bodies including the Earth. It isn't the phase per-se that causes the differences but the fact that phase and lunar orbit are closely related.
Some examples:
1) Tidal forces don't just come from the Moon. The Sun exerts significant tidal forces as well. The sum of these forces is dependent on the position (and by extension phase) of the Moon in its orbit. So you will tend to see the strongest tides during Full and New moons because the Sun and moon are (approximately) directly lined up.
2) Also the lunar orbit isn't circular so the moon will exert different amounts of tidal force on the Earth depending on its proximity. You will see different phases of the moon depending on its orbital position. Stronger tides occur when the moon is closest in its orbit to the Earth.
Forces of nature can trigger forces of nature.
Film at eleven.
We suffer more in our imagination than in reality. - Seneca
If someone actually bothered to compute the gravitational force on the Earth by both the sun and moon, you would find the force of the moon is about 1E6 times larger than that of the sun.
The Sun is roughly 400 times further way than the Moon. The Sun masses roughly 30 million times more than the Moon, We have that gravitational force is proportional (using the pretty accurate point mass Newtonian model of gravity) to the mass of the object and inversely proportional to the square of its distance. Hence, the Sun's gravitational force is crudely 200 times stronger than that of the Moon.
By a similar calculation one would get that the tidal force of the Sun is roughly half that of the Moon since tidal force under the above model is proportional to mass and inversely proportional to the cube of the distance.
So maybe there was a reason your highly accurate motion platform wasn't.
Fracking industry bought off scientists, skewed geophysical science research for decades
The moon causes ocean tides of several feet. It also causes land "tides" of several inches. This small flexing of the earth can set up conditions where a fault that is already under a lot of stress can release, resulting in an earthquake. Normal tectonic movements are the source of the stress that is slowly building up over time, but the flexing of the earth due to the sun and moon results in statistically higher releases of the stress around full and new moons. In other words, the fault was ready to rip and the gravitational forces just gave it the little extra bump that it needed.
Well just think how we can magnify that by fracking on the moon...
Really? So there's a noticeable tidal change once every 24 hours from the sun? I don't see it. What you see is motion of the oceans and tectonic plates that match the period of the moon's position.
Given that the title under which the article was posted to /. is "The moon's gravitational pull can trigger major earthquakes, says study", the cushioning was not only necessary but inadequate.
pull on the moon (basic physics). And because global warming causes earthquakes, global warming affects the orbit of Earth's moon.
So there's a noticeable tidal change once every 24 hours from the sun?
Yes. There's even centuries old names for these effects, spring and neap tide.
Just because you can't see it now doesn't mean that sailors centuries ago couldn't see it.
What you see is motion of the oceans and tectonic plates that match the period of the moon's position.
The Moon's position relative to the Sun.
An earthquakes occurs when the static force of friction at a point of geologic stress is overcome, or when the force on a geologic structure exceeds its breaking point. It is an extremely non-linear response, which can be triggered by small changes in these forces. Given that, it would be surprising if tidal effects were not correlated with earthquakes.
As the polar ice melts and its weight is redistributed over the oceans, I expect this also will result in sufficient changes in tectonic forces to trigger more earthquakes, and perhaps volcanic activity as well. It wouldn't surprise me if even changes in atmospheric pressure are sometimes sufficient to trigger a quake.
Duh.
Gravity pulls on matter.
Didn't we already know this? The moon can cause tides, earthquakes, and other Earth-bound changes.
Let's answer the REAL question, shall we? The REAL question is, how can we blame this phenomenon on anthropocentric climate change?
Craigslist killed syzygy job.
How can you predict earthquakes if you can't monitor lost pet notices in the newspaper classifieds?
Also makes it hard to hookup with timetravellers, for obvious reasons.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
If the moon's gravitational pull lifts stuff on earth, then shouldn't the earth's pull lift stuff on the moon? How is it then that the official shape of the moon looks like a lemon with the flat side facing earth?
There is no outer space & the Van Allen belts are an euphemism for solid firmament.
If the Bitcoin guy says the gravitational pull of the moon can trigger major Earthquakes, I believe him!
That's no moon!
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Have you ever lived on a coast? There is a roughly-daily cycle of tides, caused by the combination of the Moon's and the Sun's gravity. If it was only affected by the Moon, it would be just a simple cycle and the tides would always be the same height. The Sun throws off the peak times and causes higher tides near alignment and lower tides when the Moon is half full.
I wonder whether the direction of the fault and the latitude make any difference?
They're divine punishment to us all for allowing homosexuals and assorted heathens to run amok! It's true. It's all there black and white clear as crystal.
BRE
"Dude check me out. I'm like a little otter. A SEXY little otter"
Obviously it's a plan to wreck destruction upon the earth by the evil moonites. So what are we going to do about it? Lets show them our wrath and blow up the moon.